Brian Dunning’s Skeptoid does an excellent job of debunking pseudoscience, so his podcast on DDT is profoundly disappointing. Dunning claims that DDT use did not have a large impact on bird populations, that elitist environmental groups were killing brown children by blocking DDT use and that DDT is effective even if mosquitoes are resistant. None of these claims are true, as I will detail in this post. But first, why did a sensible fellow like Dunning get it all so badly wrong? Well, his primary source for information about DDT was Steve Milloy‘s junkscience.com. One commenter remonstrated:

I trust JunkScience on health and environment like I trust the Discovery Institute on evolutionary biology, or Prison Planet on history.

Dunning responded:

The JunkScience guy has a blatant libertarian agenda. The SourceWatch guy has a blatant anticorporate agenda. Big whoop! They’re both still researchers. I have no problem citing either if they’ve done the research I’m looking for.

If you must insist that this makes everything coming from either guy always right or always wrong, then you should demand to see the voting history of every scientist or researcher in order to determine the quality of their work.

This misses the point. Biased sources aren’t necessarily wrong, but they are unlikely to give you the whole picture and it would be wise to be skeptical about what they say and fact check their claims. This post is the fact check that Dunning failed to do.

Silent Spring doesn’t say anything at all about eggshell thinning since it wasn’t discovered until after the book was published.

It’s been about five decades since Silent Spring was published, and we’ve learned a lot in those years. One thing we’ve learned is that DDT is only one of many causes of eggshell thinning. Other culprits include lead and mercury toxicity, oil, phosphorus and calcium deficiency, and dehydration. Perhaps most significantly, birds in captivity in order to undergo testing are under stress, and this stress alone is enough to produce eggshell thinning. Although DDT’s mechanism for eggshell thinning is plausible, many studies throughout the 1970’s and 1980’s failed to correlate such thinning with high levels of DDT, even extremely high levels. Other studies have confirmed Rachel Carson’s findings. My own conclusion based on a review is that there probably is a correlation, but it’s not a strong one; and at best it’s only one of many causes. Whether DDT is used or not would probably not have a large impact on bird populations.

This is based on points 39-64 in Milloy’s 100 things you should know about DDT, but Dunning goes beyond Milloy’s claims with the unsupported assertion that the stress of captivity causes thinning. Dunning’s “failed to correlate such thinning with high levels of DDT” corresponds to Milloy’s points 43 and 44. These all cite obscure reports and journals so we can’t check them. Except for this one:

44 Among brown pelican egg shells examined there was no correlation between DDT residue and shell thickness.

Ah, Nature. That we can check. Here’s what Hazeltine’s letter says about that correlation:

“The CFDG data (Table 1) show a nearly perfect correlation of lipid DDE residues to shell thicknesses, and the relationship is positive.”

OK, that’s not exactly what Milloy had, but the point is that the correlation goes the wrong way. Trouble is, Milloy fails to mention that there were four responses to Hazeltine published in Nature. Let me summarize some of the problems with Hazeltine that these letters pointed out. First, Hazeltine’s CFDG data comprised just nine eggs. Those eggs mere a mixture of incubated and non-incubated, and the positive correlation is caused because incubated eggs have thicker shells and higher DDE concentration in the lipid. How? Well, incubation consumes most of the lipid and concentrates DDE in the remaining lipid. And thin eggshells are less likely to survive incubation (that’s the reason why eggshell thinning is a problem in the first place.) If you look at the relationship between whole egg DDE and eggshell thickness there is no statistically significant relationship in Hazeltine’s set of just nine eggs. But other studies with larger samples have found a significant negative relationship between DDE and brown pelican eggshell thickness. Unlike Milloy, Hazeltine cites them in his paper and states:

That DDE is the cause is of thin brown pelican or peregrine eggs is well established in the … scientific literature.”

Hazeltine tried and failed to overturn this. Milloy misrepresented the science by deliberately concealing the existence of the studies that found that there was a correlation between eggshell thinning and DDE.

Now let us examine Dunning’s next paragraph:

But despite the likelihood that it would have some impact, it’s now known that the species Rachel Carson focused on (most notably bald eagles) were already in massive decline from unrelated pressures even before DDT’s introduction. Habitat loss and hunting had been, by far, the greater causes of bald eagle deaths. Hunting had reduced the populations to just a few hundred nesting pairs in the mountains, and lowland eagles were already gone from habitat loss. Rachel Carson did not ignore these issues in her book, but the popular perception that banning DDT was all that was needed to magically restore bald eagle populations was naÃ¯ve. In the end, it was the Bald Eagle Protection Act and the bird’s 1967 placement on the endangered species list, combined with increased penalties for poaching, that ultimately led to the bald eagle’s successful return to remaining habitats.

Just 40 years ago, the bald eagle seemed headed for extinction in the conterminous United States. Nesting females were accidentally crushing their eggs, which were weakened by the ubiquitous insecticide DDT. … Banning DDT has helped the national population of breeding bald eagles to grow.

[Wildlife ecologist Stanley Temple of the University of Wisconsin] says that the return of the eagles and other raptors, including peregrine falcons and and ospreys, “is due almost wholly to the ban on chlorinated hydrocarbon pesticides.” The ban of the number one offender, DDT, took effect in 1972, eliminating a group of pesticides that thinned eggshells, causing the birds’ reproductive rates to plummet.

Reproduction of bald eagles in northwestern Ontario declined from 1.26 young per breeding area in 1966 to a low of 0.46 in 1974 and then increased to 1.12 in 1981. Residues of DDE in addled eggs showed a significant inverse relation, confirming the effects of this toxicant on bald eagle reproduction at the population level and the effectiveness of the ban on DDT. The recovery from DDE contamination in bald eagles appears to be occurring much more rapidly than predicted.

Now it is certainly true that shooting and habitat loss also contributed to the decline of bald eagles as the US FWS states:

By 1963, with only 487 nesting pairs of bald eagles remaining, the species was in danger of extinction. Loss of habitat, shooting, and DDT poisoning contributed to the near demise of our national symbol.

As the dangers of DDT became known, in large part due to the 1962 publication of Rachel Carson’s book Silent Spring, the Environmental Protection Agency took the historic and, at the time, controversial step of banning the use of DDT in the United States. That was in 1972, and it was the first step on the road to recovery for the bald eagle.

But Dunning is wrong to dismiss DDT as a cause — preservation of habitat and bans on hunting and DDT were all necessary to save the bald eagle.

On to Dunning’s next paragraph:

Brown pelicans are another species often cited as having been decimated by DDT use in the United States, along the Gulf coast and in California. Massive declines were indeed correlated with DDT use, but it may have been a coincidence in each case. Along the Gulf coast, hunting by angry fishermen had reduced the pelican population in Texas from 5,000 annual births to just 200 in 1941. The California populations suffered a double whammy in the years following Silent Spring’s publication; first with an oil spill off Santa Barbara in 1969, and then with an outbreak of Newcastle Disease in 1971 that unfortunately required the culling of millions of brown and white pelicans. DDT certainly didn’t help; but it was another case where the bird populations would have dropped sharply whether DDT was in the picture or not.

Compare with Milloy:

96 An epidemic of Newcastle disease resulted in millions of birds put to death to eradicate the disease.

[United Press International. “Newcastle disease epidemic in California (April 1972)] The epidemic among U.S. birds was caused by the migration of sick pelicans along the Mexican coast.

Note that Milloy doesn’t actually say that the birds put to death were pelicans — he just implies that they were and Dunning didn’t stop to think whether it even made sense that an endangered species would have a population in the millions.

For example, parrots from South America are believed to have caused an outbreak of exotic Newcastle disease (END) in southern California in the early 1970s. Eradicating that disease outbreak cost $56 million over a 3-year period. During that outbreak, more than 12 million birds were destroyed, the vast majority of which were commercial poultry.

In 1992, 26,000 turkeys in North Dakota were destroyed after APHIS diagnosed virulent Newcastle disease in the flock. Cormorants were the suspected source. Hundreds had died from the disease at a lake near where the turkeys were being reared on range. Seal confirmed this suspicion when he compared the genomes of turkey and cormorant isolates.

The episode was part of the United States’ first known Newcastle-related die-off of free-ranging wild birds.

So the number of pelicans dead as a result of the 1971 outbreak of Newcastle Disease was not “millions” as Dunning claimed, but zero.

As for the Dunning’s claim that the pelicans’ troubles were coincidental, this interview Professor Daniel W. Anderson of the University of California at Davis, summarizes the evidence:

DA: Dr. Ray is a little slippery when she says there is no supportive evidence of population declines and that bird populations actually increased. There are many cases, but let me mention one that I personally worked on. She does not mention one of the best case histories in North America of DDE-induced population effect which involves the decline and resurgence of the California brown pelican.

ER: California brown pelican populations were hurt by DDT?

DA: By DDE. But in this case, they were adversely affected not by DDT used as a spray but as DDT and metabolites were put into the sewage system in Los Angeles. It entered the Southern California Bight in large quantities. [A bight is a curve in the coast that forms a bay and also often entrains an oceanographic gyre. ed.] Some people in Professor Risebrough’s group looked at the sediments in Southern California and saw where DDT and its metabolites first appeared.

ER: When did DDE start showing up in the sediments?

DA: About the 1950s. It was like a detective case and when the source was discovered, input stopped pretty quickly.

ER: What was the source?

DA: The major source was found to be a manufacturing plant in Torrance.

ER: When did they make the changeover to landfill disposal?

DA: It started in about 1970. And within a year the DDE residues began a long decline in the pelicans and other wildlife of the bight and the pelicans (and other species too) started to show signs of recovery.

ER: Was there experimental work with the pelicans that showed eggshell thinning after exposure to DDE?

DA: No experimental work like controlled feeding experiments was done in brown pelicans because that species was on the endangered species list. But there was a positive relationship between the amount of DDE residue female pelicans had in their bodies at the time they were laying eggs and the amount of eggshell thinning. Similar relationships have been shown over and over again, all over the world, for many bird species and by many, many investigators.

As Daniel Anderson notes in the interview above, there were no
controlled feeding experiments on brown pelicans so you could, I
suppose, argue that the correlation between thin eggshells and DDE,
and the collapse and recovery of pelican breeding associated with the
increase and decrease in DDT use was all a big coincidence. But a1975 paper by Jeffrey Lincer
would seem to rule that out.

Here’s Figure 3 from Lincer’s paper. The x’s show that in controlled experiments the more DDE fed to kestrels the thinner the eggshells. And it shows that the same relationship occurred in wild kestrels, so it is not true that dosages used in the experiments were unrealistic.

For more on DDT and eggshell thinning see this WHO report written by expert toxicologists.

Comments

Yeah, I heard that Skeptoid and shrank when I heard him citing Milloy. Oy, vey! I thought Dunning was better informed than to trust a denialist like Milloy whose history is that of spewing misinformation and pseudoscience hither and yon to attack AGW, environmentalism, and basically anything that does not conclude what industry wants. In fact, I had thought about blogging about this, except that I don’t have as extensive a background to be able to rebut it as thoroughly.

I had a small tweeter exchange over this with Brian but he didn’t seem open to discussion. This is an ongoing issue with Brian Dunning an Michael Shermer; their judgement is clouded by a libertarian ideology. The latest skepticblog entry by Shermer is a gushing review of Lomborg’s new movie. It’s worth a read http://skepticblog.org/2010/11/16/throwing-cold-water-on-a-hot-topic/

There is an interview with Dunning in one of the recent “Drunken Skeptics” podcast. He does initially try to dismiss those who disagreed with the use of junkscience as a source as being entirely political motivated “You shouldn’t use him as a source because he is a right wing libertarian and I don’t like his politics” (paraphrasing), but after a little gentle prodding does address some of the genuine criticisms, rather than his straw man version. Still not entirely convincing though.

Biased sources aren’t necessarily wrong, but… it would be wise to be skeptical about what they say and fact check their claims.

Tim, that’s a huge “but.” How biased is biased, given that everyone is biased to some degree. This is why I’m still skeptical about the claimed impact of AGW. I don’t have the time or resources to fact check the science, but this doesn’t mean I’m willing to take the state of the art for granted either. It’s a conundrum, and comes down to trust: I don’t trust the folks who make up the current consensus, and that isn’t going to change any time soon. It seems that the majority of AGW skeptics are full of crap also, so I don’t trust them either.

Now, DDT is a different and much simpler matter. Your review of the data has been very good and it has completely changed my opinion on the problem.

Why is it that most times there’s something reaaaaaaaly wrong stated by an eminent skeptic it turn’s out they are libertarian? Shermer, Dunning, Penn & Teller… maybe even Randi, with that global warming post sometime ago.

It’s ideology trumping critical thinking, among our very own people – so sad.

I stopped listening to his podcasts when he talked about subjects I actually specilaise in. I figured if he is that wrong on the topic I know about what are the chances he is right on all the topics I trust his information.

Mark-
He has a good reputation because his episodes are normally excellent and thoroughly researched. Occasionally, they seem to touch on areas where he has a vested interested – some of the previous organic food ones, or animal welfare ones in which case he sometimes puts up straw men arguments , for example on Trader Joes “Shoppers appreciate its image of healthful food in a small-business family atmosphere.” He then goes to show that Trader Joes is in reality a typical corporate business. What he doesn’t do, is provide any evidence that this is why people like the store.
Sometimes, he seems to be wrong just because he doesn’t bother doing the research. His recent episode on boosting the immume system for example. While it is almost certainly true that companies that sell products to “boost the immune system” don’t have the evidence to back such statements, his argument that “If you could boost your immune system, it would automatically and immediately be harmful.” is equally fallacious. The idea that if you had more immune cells, or they were able to react to infection quicker, this would result in autoimmune disease seems to be made up from nothing and contrary to real world experience, where people do vary in their ability to resist disease

Ben, I am happy for you, because if this modest post about DDT (modest compared to all that could be written on the topic) was enough to convince you, then you might be one of the rare AGW skeptics susceptible to evidence.

I think this post at skepticalscience has one of the better information/wordiness ratios.

The New York Times’s “Science Times” section had an article about DDT and its apparent effects on the condor that continue to this day: http://www.nytimes.com/2010/11/16/science/16condors.html. I imagine quite a number of people have let Mr. Dunning know of the article, but I sent him an e-mail with the url anyway.

In the comments section to his DDT podcast, when people questioned the credibility of his sources, Mr. Dunning responded: “Feel free to point out any flaws you find, I’ll happily correct them.” Multiple people then proceeded to do exactly that. 3 weeks later, Mr. Dunning has yet to issue any corrections, address any of his critics’ points, or even post so much as a “Thanks for sharing, let me read your links and I’ll get back to you.” I usually find his podcasts entertaining, but his apparent inability to even consider that his critics might have a valid point is dragging down his credibility fast.

We don’t expect you to be perfect, Brian. We don’t even expect to agree with you all the time. But at least make an attempt to consider your own confirmation biases when they’re pointed out to you.

As for not only DDT in particular but chemicals in general vis-a-vis malaria, we built the Panama Canal with the assistance of sanitation engineering and other mechanical measures; not a drop of spraying involved.

So, was brian dunning condemned by fate to demonstrate the dunning-kruger effect due to his being born of unrelated dunnings?

One problem in all this is that DDT (actually, DDE) has varying effects on different species of birds, due to metabolic differences, presumably (this shouldn’t be a huge surprise, we wouldn’t expect members of the order falconiformes to flourish on a diet of cracked corn, nor those of order columbiformes to thrive on a diet of raw meat).

Junk Science makes much of early research on quail and the like showing that they don’t experience reductions in reproduction (in those early studies, at least), so therefore (of course!) there’s no drop in reproduction success due to eggshell thinning in raptors (despite all the research to the contrary).

Some years back a paper was published on the analysis of brown pelican eggshells which showed that there were structural differences even in those that showed no (or miminal, I forget which) thinning, making the shell more permeable to water, potentially leading to the eggwhite drying out during incubation. But I’ve not been able to find the damned thing online.

Anyway, I raise that to point out that eggshell thinning isn’t necessarily the *only* change caused by ingestion of DDE by female birds.

There are few things in science as throughly pinned down as the relationship between DDE and reductions in reproductive success in raptors and brown pelicans.

(fortunately the argument that “PCBs do it, too!” led to the phase out of use of PCBs here in the US, rather than the resumption of widespread DDT use in agriculture!)

I don’t trust the folks who make up the current consensus, and that isn’t going to change any time soon.

That’s an awful lot of people to distrust; what, between 1000 and 2000 people? Pretty much everyone in an entire field of science in various nations around the world? Do you have a reason? Is there any evidence of untrustworthiness?

The chief problem with Milloy’s page is that so much of it is pure fiction. Some of the fiction is tangentially related to reality — notice how Tim can find some of the sources and track them down — but most of it is simply made up excrement.

Milloy got it from Gordon Edwards. Edwards had tried to publish some of his rants against Rachel Carson, but stopped when editors wouldn’t.

I challenged Dunning to check up on Milloy’s sources, and to the best of my knowledge he has failed to do it.

Others should, however. It’s shocking. On counts of eagles and other birds, for example, Edwards/Milloy claim that counts of eagles and falcons and hawks actually rose during the heavy DDT use era.

They cite Audubon Magazine.

It’s a slog, but you can check every bird count from 1935 through 1975, and you will not find a claim from Audubon that the populations of those birds rose at that time. It’s possible to see how a deceitful person could abuse the bird counts to reach such a conclusion — if there are more observers, there are more sitings — but if you cross check the Edwards/Milloy claims with those numbers, they still don’t produce an increase in populations.

And then there is the issue that, in a period when Edwards claimed to find one article claiming an increase in eagles, there are no such articles, but perhaps two dozen decrying the loss of the birds, and more articles decrying the devastating effects of DDT, and it’s difficult to conclude that whoever put that piece together, Milloy or Edwards, was just lying to see if anyone would bother to call a bluff.

Serious researchers must check citations of sources, especially when the cited claim runs contrary to all other evidence. Dunning failed to do that, and hasn’t yet, so far as I can see.

Libertarian, conservative, liberal, religious — I don’t care what your political views, if you’re going to get hornswoggled so badly, you need to back up and re-educate yourself on how we know what we know.

Socratic Gadfly @24 – at least Dunning is not a racialist like Shermer might be. On one of his answers to student questions episodes he responded to a question about athletic ability and race by starting out with the concept that race is a social construct.

Shermer showed himself to be a pseudo-skeptic with his claims that the economic meltdown was due to regulation rather than de-regulation. I guess he didn’t notice how the much more regulated Canadian banks didn’t require one cent of bailout money.

Does Milloy get paid to spread disinformation? – he sure comes across like a professional contrarian liar for hire.

Tim, that’s a huge “but.” How biased is biased, given that everyone is biased to some degree. This is why I’m still skeptical about the claimed impact of AGW. I don’t have the time or resources to fact check the science, but this doesn’t mean I’m willing to take the state of the art for granted either. It’s a conundrum, and comes down to trust:

[My bolding, Ben’s italics]

Well, reserving your opinion on AGW is fine if you don’t feel that you have managed to acquire an adequate and reasonable accurate (ie reliable) knowledge on the subject; however, scientists beavering away in a university environment – which includes long field trips to remote locations – and who regularly publish their research allowing open scrutiny from other scientists, are seriously way more reliable than the deluded deniers (who are to skeptics as Tea Partiers are to Republicans) who have an ideological aversion to AGW, as that is where the Reds – now the Greens – congregate, metaphorically speaking.

In other words, some bias is sustained by an echo chamber of like-minded ideologues, while other bias is mutually crushed through attempted replication, criticism and follow-up studies. Science isn’t perfect and is often slow in arriving at results solid enough to keep most scientists happy; and really, that is the best we can expect.

>I don’t have the time or resources to fact check the science, but this doesn’t mean I’m willing to take the state of the art for granted either. It’s a conundrum, and comes down to trust: I don’t trust the folks who make up the current consensus, and that isn’t going to change any time soon.

There is no conundrum. If you were to fact check the science, you’d find out the scientific mainstream is by far the most reasonable position. That’s why it’s the mainstream.

This whole thing applies to AGW as much as DDT and a whole bunch of politically contentious issues. It distresses me that so many people take the intellectually lazy option of picking and choosing the opinions of think tanks and pressure groups to get the material that suits their own world view. But it also distresses me that many self-professed ‘sceptics’ seem to think the road to truth consists of weighing up one side of the argument against another, debate-style. There’s invariably a wealth of material out there in the scientific literature and you can only really get the complete picture if you are willing to get your hands dirty.

Personally, my most trusted started point for most subjects tends to be the learned societies followed by the review journals. These have reputations for impartiality to maintain, so they tend to be the most diligent.

“I stopped listening to his podcasts when he talked about subjects I actually specilaise in. I figured if he is that wrong on the topic I know about what are the chances he is right on all the topics I trust his information.” (Mark #9)

Ditto, except I started with a couple of podcasts on my subjects & never bothered to listen to any others given that in some aspects he was – to coin a phrase – not even wrong.

One thing I learned while researching this episode is that it is a topic that really underscores the ideological gap between liberals and conservatives. I am often surprised, quite naively, at the way so many people let their politics determine their science.

The other thing I learned is that there are a HUGE number of studies on DDT that contradict one another. Anyone who says the evidence is clear one way or the other has not spent a lot of time trying to falsify their preexisting notions. None is more guilty of this than Steven Milloy, but he’s not the only one.

The assertion that I quoted Steven Milloy is bizarre. I added his page to the Further Reading suggestions after the episode was produced and posted. I had never even heard of him while researching the episode — which is symptomatic of the fact that there’s only so much time I can spend on each weekly episode and my research will never be as complete as I wish it was.

I note that one commenter says I “quoted Milloy and got busted for it”. You’ll find that in EVERY Skeptoid episode, I quote both sides. Or at least I try to. “Busted” for presenting the dissenting viewpoint? Nope, sorry, find another podcast if you demand only side to the story.

(For all those who wrongly think that I quoted or cited Steven Milloy, in any way, please see the note appended to the transcript: http://skeptoid.com/episodes/4230)

>You’ll find that in EVERY Skeptoid episode, I quote both sides. Or at least I try to.

I refer back to my previous comment. Science should never be about ‘sides’, it should be about facts. Sure, there are lots of people disagreeing about lots of things, but if you let the ideologues frame a discussion you’re only going to end up comparing one distorted world view with another.

The assertion that I quoted Steven Milloy is bizarre. I added his page to the Further Reading suggestions after the episode was produced and posted. I had never even heard of him while researching the episode

That means that a lot of the claims you made are completely unsourced, or (at best) based on an unsourced newspaper article written by an economist.

Where did you find the claim that millions of brown pelicans were killed as the result of an outbreak of Newcastle Disease, for example? Or the claim that three million people a year die of malaria?

Also, how is one supposed to understand which parts of the “References and Further Reading” section are actual references that you used to support your argument, and which are mere “further reading” that might possibly say something on the topic? Is it really unreasonable for a reader to assume that a resource listed in this section might have been used as a reference? Especially if you’re citing claims that originated with that resource?

OK, but the post you’re commenting on doesn’t claim that you did. Tim Lambert isn’t making the transparently false statement that you quoted Milloy in your podcast or even said Milloy’s name. What Tim said is that Milloy was your “primary source for information about DDT” and he gave some examples where you appeared to rely on Milloy. Do you have a response or do you just intend to attack straw men?

I get that you don’t have unlimited time to follow up on each podcast, but you know this issue is a little more important than whether frogs can live in solid stone or the Yonaguni Monument was man-made. Getting DDT right has very big consequences for human welfare and the environment.

When I was younger (so much younger that today), being of a sceptical bent, I encountered Steve Milloy’s Junkscience site and thought “at last – intellectual liberation!”!

It was not long until I realised the guy was a complete fraud and drummer for the fossil fuel industry (and anyone else that pays him, like tobacco companies).

Doubt set in immediately I read in one of his articles that once could not define an average measurement (like temperature) over a sphere (like the earth). Since I had a smidgin of mathematics and maths physics, I knew that was complete garbage.

@Mark (#9) and @Chris S. (#35) I too had to stop listening to Dunning’s podcasts and have advised my student generally against listening to them as well, except as examples for Sagan’s Baloney Detection Kit. Same thing as each of you mentioned, when I heard episodes that wandered into my areas of work, they tended to be full of straw men and pretty awful. Plus he comes off as a total jerk when his errors are pointed out (see #36 above – which isn’t full flower but gives you an idea).

His statement “when I find the research that I am looking for” certainly comes off as an active demonstration of cherry picking and confirmation bias. He also, based on his broadcast, didn’t actually read Silent Spring, or was not paying any attention when he did.

I agree that the issues are not perfectly clear, they almost never are, but this podcast does absolutely nothing to improve the situation and what politics has to do with any of this is totally beyond me … have condors been voting Democratic ? Total nonsense.

I used to like listening to his podcasts on some of the wilder woo woo beliefs out there, but even those have become tainted. He has turned into Faux News – wrong and arrogant about it.

You screwed the pooch on this one. Whether you directly quoted Milloy or not, you presented an argument that was incorrect from start to finish. Instead of refering to conflicting studies, why don’t you do some real fact checking, and then publicly correct your errors?

There are enough studies linking DDT to egg shell thinning to eliminate any real doubts about this. Yet you seem to rely on one study that used only 9 eggs, and conflicted with numerous other studies as well as repeated correlation between the two in the wild. If you didn’t ignore the main body of research for one flawed study, provide your sources. As for having only so much time to work on these things, that is no excuse for shoddy, poorly conceived propaganda.

It is amusing in a sad way that folks like you are still fighting Rachel Carson. It is more amusing that though she has been gone for 45+ years, she is still kicking your behinds.

This argument puts you in the same category as the moon landing hoaxers. Congratulations on that, you sceptic you.

As a former vector control professional, I have to disagree with Mr. Dunning. Overall, the evidence shows that DDT has serious problems and should only be used under the specific conditions laid out by WHOPES and the Stockholm Convention.

Possibly the Dunning program needs help with fact checking, and could get it for the asking.

I gather Dunning has become popular with people who like that kind of thing–if so they have to look out harder for efforts to use them as a vehicle for bad information.

The last paragraph of the transcript talks about using DDT “in Africa” and I’d bet that’s the trick. As ‘Bug Guy’ says above, adding “under the specific conditions …” would have been a smart conclusion.

I am often surprised, quite naively, at the way so many people let their politics determine their science.

I’m glad you finally decided to weigh in on the issue, Brian. But it seems to me you’re the one who brought politics into the mix, both in your comments thread and in the Drunken Skeptics podcast. No one is saying they don’t like your politics – they’re saying you did sloppy research. Some folks have suggested it may be due to (completely human) confirmation bias reinforced by political ideology; but the issue is the poor research, regardless of its underlying cause.

The assertion that I quoted Steven Milloy is bizarre….I had never even heard of him while researching the episode

In that case, I think it would be hugely helpful if you clarified what sources you actually did use for your claims that have been challenged. If you weren’t relying on Junk Science for your information, where did you get it? Please list the “HUGE number of studies” that contradict the scientific consensus. I know you have a limited time to research each podcast, but seriously, dude – your credibility is on the line here.

This is all about the rehabilitation of DDT’s reputation, which is part of Libertarianism’s broad anti-science campaign in support of its anti-regulation dogma. Dunning is a spear carrier in that crusade.

Dunning is no more a skeptic than is Penn Jillette. In fact he’d be a nice fit over at CATO, where he could sit with Jillette at Patrick Michaels’ knee and absorb “knowledge” suitable for libertarian sensibilities.

Okay – I have clearly been spending too much time in my ivory tower (i.e. windowless closet of a laboratory). Could someone explain the libertarian connection here? I understand that the general libertarian meme is “smaller government” and “less regulation” so that translates into “companies should be able to do whatever they want”? I suppose that would explain why someone billed as a skeptic has been so hysterical about things like local/organic foods etc. Talk about deep cover. Can someone point to something that gives some perspective ?
Thanks

My distaste for Milloy’s tactics are heightened by my experience staffing the Senate Labor Committee during a round of the great tobacco wars, when the warnings on cigarette packages were increased in number, and rotated. Milloy’s work in favor of DDT, a largely ineffective chemical popular in a completely ineffective malaria-fighting strategy, uses exactly the tactics of misleading press releases and deceptive claims used by the tobacco companies back then.

I expect skeptics to have learned something about propaganda over the years.

There is a huge number of studies showing the harms of DDT. There is a huge number of studies verifying that DDT is no panacea against malaria. There is not much, in the science journals, to the contrary.

Among many other bullshit tropes from the self-proclaimed skeptics, they all hate the animal-rights anti-cruelty people. They claim an essentially Old Testament right to do whatever they want to to animals, for whatever reason (combined with a propertarian view of nature). But in fact, the scientific, evolution-based conclusion is that many animals are quite similar to us, feel similar pain, and therefore, if your ethics involve not being cruel, you should at least give some weight to non-cruelty. That’s no more scientific an attitude than some animal-rights people’s claims that animal research is almost never effective.

In the real world, without some anti-cruelty advocacy, the market and competitive research pressures will set the norms, and there will be no incentive to justify research goals and methods.

As a former vector control professional, I have to disagree with Mr. Dunning. Overall, the evidence shows that DDT has serious problems and should only be used under the specific conditions laid out by WHOPES and the Stockholm Convention.

If that had been Mr. Dunning’s intention, why would he rely on the propaganda from the critics of WHO and the Stockholm Convention, the propaganda that claims WHO is a bunch of bumbling mass murderers, and that the Stockholm Convention is a racist screed that guarantees lots of dead babies in Africa?

And Milloy IS paid to spread disinformation. That’s, literally, his job. He’s quite often compared to the protagonist of “Thank You for Smoking.” He’s spread disinformation on tobacco, pesticides, food, pollution, and global warming, among others. He’s also not a scientist, not scientifically versed, and most of his campaigns are explicitly anti-science. I agree completely with those saying if anything Tim Lambert is giving Brian Dunning too much credit, when he deserves none.

Mark, I would like you to expand, too. G. Shelley, what percentage of his episodes are thoroughly researched? Please give an example of one, because at this point, I’m skeptical.

Brian, I did not state that you quoted Milloy, but rather that he was your source. I showed this with quotes from your podcast and quotes from Milloy’s page that was your source. None of the other references you gave contained that information.

The claim that brown pelicans were the source of the Newcastle Disease outbreak puts the matter beyond doubt. All other sources that I could find say that the source was imported parrots. Milloy is the only one who blames the pelicans. And your claim that millions of pelicans were culled is unique to you, but is clearly based on a misunderstanding of Milloy.

Dunning is right about there being lots of contradictory studies in the literature on DDT. This is especially true of the early eggshell literature, when scientists were still sorting this all out. And so one could be forgiven for concluding, after browsing primary research articles for just a few hours or even a few days, that the question of DDT’s effects on eggshells hasn’t been settled. But one would be wrong. Scientists have spent entire careers studying this, and they understand the issue far better than someone with a week a to put together a podcast ever could. And what do these people say? They say the DDT/DDE/DDD causes eggshell thinning in certain bird species. The Agency for Toxic Substances and Disease Registry (and arm of the U.S. CDC) put together a great “toxicological profile” on DDT/DDE/DDE which was published in 2000. Appendex D, section 6 (page D-24 of http://www.atsdr.cdc.gov/toxprofiles/tp35.pdf) has a nice synthesis of the science on DDT and eggshells. And what these experts conclude from the sea of studies (that to the untreated appear contradictory) is that DDT/DDE/DDD causes eggshell thinning.

Point is, Dunning can draw his own conclusions, but the real experts in the field–the folks who have spent more than a week researching and who have PhDs in relevant disciplines–these folks all agree that eggshell thinning is real, and it’s caused by the use of DDT.

Okay – I have clearly been spending too much time in my ivory tower (i.e. windowless closet of a laboratory). Could someone explain the libertarian connection here?

The chief source of Libertarian cant in the U. S. is the Cato Institute. Funded chiefly by the fossil fuel billionaire Koch brothers, it disseminates science disinformation on a number of issues with the goal of using doubt to derail regulation. DDT, climate change, secondhand smoke, recycling, all are subjected to spin and propaganda from Cato.

For Libertarians like Dunning, it sets the agenda. The results can be seen in the Skeptoid podcast under discussion.

pHred: the ‘ibertarian connection is the argument that people will make free market choices to avoid personal problems.

Problems such as air pollution; second-hand smoke; lead in drinking water systems; chloramine interacting with melamine to make insoluble crystals in kidneys; DDT bioaccumulation from sediments; fake bolts in aircraft; etc.

The concept is that when individual people, as Tom Lehrer put it, “don’t drink the water and don’t breathe the air” their personal choices will cause the free market’s invisible hands to sell fewer cheap dangerous products.

Remember the observation, by a banker named David Hannum: “There’s a sucker born every minute.”

Okay – totally weird. You would think that a group with a banner like “Individual Liberty” would be for things like locally based economies. Clearly in this case “individual” = individual corporation and not individual person.

I will read further – but right now I am supposed to be grading papers for a class in which, ironically, we actually watched a biography of Rachel Carson last time. I might just play this podcast for the class to critique.

Not to be a pest, have Dunning et al. self identified as Libertarians ? I have been peripherally aware of them but have not looked in too much detail. It is hard enough to find out enough about local candidates to cast a sensible vote with sorting this stuff out too. Clearly though it appears to rot out irony meters and self-awareness. (Oh right – Rand Paul was the one “for” civil rights unless they offended you personally – UGH!) I will have to start paying more attention to this affiliation.

OMG! Shermer jumped the shark for me years ago but I had no idea that he shot the shark on the way over. Seriously, he supports Lomborg ?!? A man who’s short articles are full of enough misrepresentations and nonsense to choke a horse? Wow.

BTW – would you people stop distracting me! I am supposed to be grading papers! I have to get back to my hedonistic ivory tower.

I never noticed Dunning call himself a US brand Libertarian myself. There are some people who look into and dislike woo, I suspect, that can’t help but note the overlap with batshit hippies and extreme greenies and it starts to get on their nerves. They lose trust in everything from that ‘side’. Some tilt towards those who despise the green movement and all it stands for starts to result during their search for a “neutral” source on traditionally green subjects.

Just idle speculation, of course. He didn’t say outright that DDT was safe after all, just apparently incorrect on the harm info. So its a case of false balance on DB’s part, from my detached perspective.

I can’t say for Dunning, but Shermer certainly has. His posts at Skepticblog have been nothing but essays on Libertarian for awhile now; personally, I stopped reading them after his post on how we wouldn’t have traffic problems if we just privatized all the roads. (!?) Too bad, as I really used to have respect for the man.

Let’s not tar all Libertarians with the same brush, tho. There are plenty of reasonable, moderate libertarians out there; I’d submit SciBlog’s own Ed Brayton as one example. But just like any movement, there are some people who take a basically-sound idea and elevate it to the status of Absolute Ideology That Must Always Be Right. A useful reminder that we all have our blind spots, and none of us are always as rational as we like to think we are.

The overlap between libertarianism and Big Science enthusiasm, which many Skeptics of Skeptics Society type have (as opposed to science that, for example, says there are limits to the amount we can pollute, or that indiscriminate industrialisation is bad for us) can most simply be explained by exposure to Robert A. Heinlein (or, in extreme cases, Ayn Rand) during puberty without appropriate prophylaxis. One suggested treatment is regular doses of Ursula Le Guin, combined with readings of Greg Benford’s “Timescape” and Norman Spinrad’s “The Iron Dream”. It has to be said, though, that unless the patient has shaken off the infection by the time they reach full physiological adulthood, the chances of recovery are slim.

This experimental study was designed to test an hypothesis that the primary mechanism by which DDE caused hatching failure in Common Terns (Sterna hirundo) was by disrupting the structure of the eggshell, leading to reduced exchange of O2 and CO2 through the shell to and from the embryo. In the study, gas exchange through two groups of Common Tern eggshells was reduced by 12% or 28% by sealing parts of the surface with acrylic resin. Contrary to predictions from the hypothesis, all treated eggs hatched and there were no other changes in breeding success relative to untreated controls. The result suggests that DDE caused embryonic deaths in Common Terns by mechanisms acting within the egg rather than by modification of the structure or respiratory properties of the shell.

So apparently changes in permeabilty to O2 and CO2 (not H2O)
have been detected in Common Tern eggshells, leading to a hypothesis that this was causing mortality, in turn leading to the experiment described above.

Anyway, looks like there’s still a lot of interesting research going on.

It seems like this post is all factional banter, tit-for-tat attempted cleverness and one-upmanship. Is anyone here an
entomologist or malariologist, or epidemiologist, or public health practitioner who has worked in the field, or are you just armchair commentators? DDT should be used for IRS spraying, because it’s effective in stopping malaria. Are you all against its use for this purpose?

This posts, and many of the pertinent comments are citing scientific evidence to support their case.

Brian’s case is also an object lesson to caution against spouting off with poorly supported claims based on flawed evidence on an issue of great importance for life.

If you want to debate the best treatment for Malaria, that is important too, and has been covered in different posts on Tim’s blog. However don’t try and detract from the gaping hole exposed in the claims made by Carson bashers.

I don’t see any mystery as to why Libertarians would tend to be anti-AGW, any more than Progressives tend to be pro-AGW.

Libertarians have seen intrusive (though well-meaning) governments making a codshead of everything from education and health care to national defence, and are hence suspicious of any decrees from on high which tell them “The debate is over; this is what we must do.”

Collectivists believe implicitly in the benign power of central authority to bring benefit to the masses; it is this *process* that Progressives believe in, where Libertarians are more concerned with *result*.

To suggest that a Libertarian view “clouds” a person’s thinking any more than a Collectivist view, would be to misunderstand the situation.

Rick, I would contend that your attractively simple hypotheses is wrong by testing it as follows:

Is the disaster that is the US’s Hleathcare “system” a result of too much, or too little government interference.

Your “collectivists”, “benign power” and “the masses” just sounds like nonsense from a C20th political tract.

If Libertarians were concerned with the *result* of unrestricted consumption of fossil fuels and unrestricted contamination of our environment, they would be calling for action to reduce pollution, not peddling lies to delay the inevitable.

Rick, it is fallacious to view the debate soley through the political lens. The critique of the libertarian politic was made in the context of Libertarians getting the science demonstrably wrong (again).

If you want to make the case for equivalence, then you need to make a credible scientific case. You havn’t

I doubt whether you are likely to see anything much at all if you think Libertarian vs Progressive ideology (as you put it) is solely or principally about the size of government. There is also the tiny little issue of class interests that has an unfortunate habit of rearing it’s head rather often. It is very much a matter government policy rather than just government size.

As for “governments making a codshead of everything from education and health care”. Who says? I’ll take universal healthcare and free public education any day over the alternatives. Just because something isn’t perfect, doesn’t mean it’s not better than the other options.

@Militant Agnostic No 32 – Yes, Milloy does get paid, primarily by Big Tobacco and Big Oil, as filtered through right-wing think tanks like the George Marshall Institute and the Heartland Institute.

I strongly urge reading a new book, “Merchants of Doubt.”

@WScott – Ed’s libertarianism doesn’t interfere with his skepticism.

One other note – Skeptic’s Frank Miele is, IMO, a “racialist.” And, Shermer supports him, and he’s been a senior editor there for years. That goes beyond even libertarianism. Miele’s “Race” was “Bell Curve lite,” or not-so-lite, even, in places.

Yep, Skeptic mag has an editor who believes that people with black skins are permanently stuck with deficient genes for intelligence.

Re: 70 “Is anyone here an entomologist or malariologist, or epidemiologist, or public health practitioner who has worked in the field”

I am.

“DDT should be used for IRS spraying, because it’s effective in stopping malaria.”

Not as effective as it once was, definitely not as effective as other methods.

Perhaps, rather than pontificating about “banter, tit-for-tat attempted cleverness and one-upmanship” you should maybe do a bit more research yourself. It’s evident that you are not “an entomologist or malariologist, or epidemiologist, or public health practitioner who has worked in the field”

> Libertarians have seen intrusive (though well-meaning) governments making a codshead of everything from education and health care to national defence

Obviously you can’t be from the USA.

They’ve made a codshead of national defence because they’ve outsourced their work to Haliburton and Defence Contractors.

They’ve made a codshead of education by not funding it.

But if the free market can do better, please show me where it has.

NOTE: you’re going to have to take into account the fees paid for education and add that on to the tax burden. After all, one way of making a codshead is to spend a freaking tonload of money on it for little gain.

Is anyone here an entomologist or malariologist, or epidemiologist, or public health practitioner who has worked in the field.

I am, as I mentioned before.

DDT does have its uses in a vector control program, as described by the WHO Pesticide Evaluation Scheme. For situations where there are no reasonable alternatives and where the mosquito population is not resistant to DDT, it is recommended. However, there does need to be adequate infrastructure in place to prevent diversion, properly apply the material and to handle cleaning it afterward. Handling of rinsates is also critical.

Okay, WScott. Money doesn’t make things better. Let’s switch the funding of inner city schools: they’ll get the funding the suburban schools do, and the suburban schools will get the inner city funding. Then we’ll let it run for a few years.

@ dedicated lurker 92: Wow, what did that poor straw man do to you to deserve such a whacking? I never said money was irrelevant. Nor was I talking about disparity in funding between individual schools. I was addressing the notion that the problems with our educational system are primarily due to insufficient funding, a notion that is not supported by the data. What’s needed is deep institutional reform, not just throwing more money at the problem.

“The libertarian connection”: For one thing (not all of it) start with low empathy. One aspect of libertarianism is that it is a semi-philosophical system that helps people with low empathy to believe that low empathy is hardly distinguishable from being smart (hence low empathy types like it). Low empathy also leads to looking down on anything of a do-good nature.

That’s just one type of libertarian. I don’t like labelling of people but there are people who call themselves libertarian and they are not nutty or do not have low empathy. Others are completely blinded by the ideology and let their ideology decide for them, e.g., by believing in the market magic. The worst offenders are people like Shermer for whom the ideology makes them evidence proof.

In the discussion on libertarianism or not, let’s not forget that the term “libertarian” these days is often used in a context (much like “conservative”) that is markedly different to it’s use in political theory or how it was perceived in decades past. Today’s self-confessed “libertarians” have a distinct, or at least noticeable, authoritarian slant. For a very good and concise analysis, refer to the political copass site: http://www.politicalcompass.org/analysis2

> I was addressing the notion that the problems with our educational system are primarily due to insufficient funding, a notion that is not supported by the data.

I guess if you beat the data up hard enough, it’ll say whatever you want.

> Actually, since the 1970s the US has doubled the amount of money we spend per-student, with minimal-if-any improvements in performance.

Now why does that not surprise me?

Money is pouring in to military budgets, yet the success of the wars has shown little, if any, improvement.

How much money PER CAPITA is going in to the school system compared to the average wealth?

It’s going down.

There are more shinies to spend money on (computers for every child).

Now, to show how much difference funding makes, look at the government run schools in districts that have high average earnings and compare to that of low income areas.

Remember: in the USA the funding of schools depends on the wealth of the people in the catchment area.

Look at the better grades in the better funded schools.

Same government control. Same government.

Look at the better funding of schools in France and you see better levels of education.

But libertarians don’t want to pay for other people’s education.

Despite the fact that an educated workforce is more productive and that a white-collar worker will return a better ROI than a blue collar or janitorial staff, therefore the ones with wealth make money from each and every educated member of the workforce, whereas the workforce itself (unless wealthy enough to have significant investment income) benefits from only their own and is negatively impacted from the education of others increasing the competition for better paying jobs.

Because for many espoused libertarians, the long view is invisible, the “rising tide” lifts their boat less and lifts others more than their preferred alternatives.